If you are engaged in an act of cruelty, there is an easy, effective way to silence your critics and snatch some space to carry on. Tell ...

Halal: Cruelty by Islamic faith practitioner

If you are engaged in an act of cruelty, there is an easy, effective way to silence your critics and snatch some space to carry on. Tell us all that your religion requires you to do it, and you are "offended" by any critical response. Erect an electric wire fence around your nastiest actions and call it "respect".

There's a good example of this religious modus operandi playing out on a dinner table near you – and this week, we found out it is becoming more and more common. In Britain, it is a crime to kill a conscious cow or sheep or chicken for meat by slashing its throat without numbing it first. The reasons are obvious. If you don't numb an animal, it screams as you hack through its skin, muscle, trachea, oesophagus, carotid arteries, jugular veins and major nerve trunks, and then it remains conscious as it slowly drowns in its own blood – a process that can take up to six minutes. So we insist that an animal is stunned before its throat is slashed, to ensure it is deeply unconscious. There isn't much humanity in our factory farming system, but this is – at least – a tiny sliver of it, at the end.

But there is a loophole in the law. You are allowed to skip all this and slash the throats of un-numbed, screaming animals if you say God told you to. If you are Muslim, you call it "halal", and if you are Jewish you call it "kosher". Back in the Bronze Age, or the deserts of sixth-century Arabia, it was sensible to act this way. You needed to know your meat was fresh and the animal was not sick, so you made sure it was alive and alert when you killed it. As Woody Allen once said, it wasn't so much a commandment as "advice on how to eat out safely in Jerusalem". But we have much better ways of making sure meat is fresh and healthy now. Yet for many religious people it has hardened into a dogma, to be followed simply because it was laid down in their "holy" texts long ago by "God".

Of course, they claim that this practice isn't cruel at all. Henry Grunwald, chairman of the main body overseeing the certification of kosher meat, Shechita UK, says that when you slash an animal's throat "there is an instant drop in blood pressure in the brain. The animal is dead." Similarly, Raghib Ali, of the Oxford Islam and Muslim Awareness Project, says: "It's not cruel, it is better for the animal."

This has been proven by science to be false. The Farm Animal Welfare Council (FAWC) is the Government's senior panel of independent scientific experts on this area, and their investigation found that "the prevailing scientific consensus that slaughter without pre-stunning causes very significant pain and distress". The FAWC chairwoman, Dr Judy MacArthur Clark, explains: "To say [the animal] doesn't suffer is quite ridiculous."

To give just one example: after you cut a calf's throat, in 62 per cent of cases, large clots form at the back of its carotid arteries, which means blood pressure to the brain massively slows and the animal doesn't black out at all. It stays conscious as it bleeds to death from its throat in agony.

Kosher butchers never numb their animals. Most halal butchers now use some stunning, but the RSPCA warns that it is at a much lower dosage to guarantee the animal is still alive when it is killed – so it doesn't properly protect them from pain. The attempts by religious people to explain this away and claim it is in fact a kindness to the animal are a pseudo-science: the intelligent design of animal welfare. That's why making meat like this is a crime in countries from Spain to New Zealand, where an ethnically Jewish Prime Minister banned it this year.

Yet in Britain this kind of animal cruelty is becoming standard. Over the past few years, there has been a dramatic abandonment of the numbing of animals before killing them, in the name of "respect" for a religious minority. The BBC's You And Yours programme says that halal meat now "accounts for around a quarter of the UK's meat trade". It is served unlabelled and as standard meat in Wembley Stadium, Twickenham, on all British Airways flights, at Nando's, Subway, KFC, Pizza Hut, Domino's Pizza and even swanky Ascot racecourse. There has been a huge expansion, then, in the suffering of living creatures – and we are supposed to applaud it as an advance for tolerance.

The halal and kosher meat industries are fighting even tepid proposals by the European Union to ensure that all meat made from unstunned animals must be clearly labelled. They claim this will render their businesses "economically unviable". Isn't that an extraordinary confession – that if people knew what they were buying, the companies would go bust?

Atheists who criticise religion are constantly being told we have missed the point and religion is really about compassion and kindness. It is only a handful of extremists and fundamentalists who "misunderstand" faith and use it for cruel ends, we are told with a wagging finger. But here's an example where most members of a religion choose to do something pointlessly cruel, and even the moderates demand "respect" for their "views". Their faith makes them prioritise pleasing an invisible supernatural being over the screaming of actual living creatures. Doesn't this suggest that faith itself – the choice to believe something in the total absence of evidence – is a danger that can lead you up needlessly nasty paths?

Britain is famously a nation of animal lovers who turn doe-eyed and gooey at the sight of any furry creature. So why are we sitting silently while our treatment of many of our animals regresses to the standards of the sixth century?

It is true that, at the moment, there is a frightening rise in real bigotry against Muslims and, to a lesser but still significant extent, Jews. Some people who object to the rise of halal meat try to fit it into a preposterous narrative where Britain is somehow being "taken over" by the 4 per cent of its population who are Muslim, presumably via the Protocols of the Elders of Mecca. I have written many articles against this resurgent bigotry, and I can see why some people would be shy about anything that would look like piling on.

But the only consistent position is to oppose viciousness against these minorities, and to oppose viciousness by these minorities. The proponents of halal and kosher meat are choosing to inflict terrible and unnecessary pain on living creatures every day. It would be condescending to treat them as victim-children who are exempt from moral debate – and it would be a betrayal of the real victims here: the sentient creatures having their throats cut.

We need to be much more self-confident in criticising religious claims. Your ideas do not deserve any special status because you say they came from an invisible, supernatural being.

No, we don't respect your desire to needlessly torment animals because some hallucinating desert nomads did it centuries ago. We don't respect it at all. You can cry that we are "persecuting" you if we stop you committing acts of cruelty if you want.

It's what the religious – Christian, Jew and Muslim alike – did when we stopped you tormenting women and gays and anybody else you could get your hands on. One of the great markers of the advance of human kindness is the howls you will hear from the Men of God.